Method and apparatus for electrotherapy drug delivery

Abstract

The present invention is directed to a method and apparatus for an electrotherapeutic system including a first and second electrode. Each electrode includes a respective resistance wherein during operation of the electrotherapeutic system, an electrochemical reaction involving one or both of the electrodes varies the respective resistance of at least one of the electrodes.

What is claimed is: 
     
       1. A method for providing an ionic medicament to a patient through iontophoresis, the method comprising:
 applying a drug delivery system to the patient, the drug delivery system comprising:
 a first electrode; 
 a first hydratable matrix operably attached to the first electrode, the first hydratable matrix comprising the ionic medicament; 
 a second electrode; and 
 a power source operably coupled between the first electrode and the second electrode and configured to deliver current from the first electrode to the second electrode; 
 
 delivering, in a first stage, current from the first electrode to the second electrode such that the ionic medicament is delivered to a patient through iontophoresis, and an electrochemical reaction occurs at the first electrode causing electroplating of the first electrode; 
 causing, in a second stage, the electroplating of the first electrode to increase a resistance of the first electrode such that current is no longer delivered from the first electrode to the second electrode stopping delivery of the ionic medicament, 
 wherein the first electrode, the second electrode, and the power source of the drug delivery system are configured such that a duration of the first stage delivers a predetermined dose of the ionic medicament. 
 
     
     
       2. The method of  claim 1 , wherein the first electrode comprises a metallic electrode. 
     
     
       3. The method of  claim 1 , wherein the first electrode comprises Ag (silver). 
     
     
       4. The method of  claim 3 , wherein the first hydratable matrix comprises a sodium chloride solution. 
     
     
       5. The method of  claim 4 , wherein the first electrode is electroplated, during the first stage, with an AgCl surface layer. 
     
     
       6. The method of  claim 1 , further comprising a second hydratable matrix operably attached to the second electrode. 
     
     
       7. The method of  claim 6 , wherein the second hydratable matrix comprises a non-drug ionic electrolyte. 
     
     
       8. The method of  claim 1 , further comprising a current regulator connected between the first electrode and the second electrode. 
     
     
       9. The method of  claim 8 , wherein the current regulator comprises a resistor. 
     
     
       10. The method of  claim 9 , wherein a value of the resistor is selected based on a power source voltage, a maximum required current, or an application of the electrotherapeutic system. 
     
     
       11. The method of  claim 1 , wherein the first electrode and the second electrode are printed on a substrate. 
     
     
       12. The method of  claim 1 , wherein the first electrode comprises a first metallic material and the second electrode comprises a second metallic material different than the first metallic material. 
     
     
       13. The method of  claim 1 , wherein the first electrode comprises a first metallic material and the second electrode also comprises the first metallic material.